Coastal Metal Roofing in Malibu, Chosen for the Salt Air

What Salt Air Does to a Roof

Malibu's marine layer carries fine salt particles inland on most days, and spray reaches the beachfront and bluff-top homes directly. Salt on its own is just a deposit. Salt plus moisture is an electrolyte, and an electrolyte sitting on metal is how corrosion starts. On the coast that combination is there nearly all the time: damp mornings, a film of salt, then sun that dries it and leaves a little more behind.

Rain rinses most of the roof clean in winter. The trouble spots are the places rain never reaches: the underside of eaves, the back of a parapet, the sheltered side of a chimney, the overhang above a deck. Salt builds up there and stays wet longer. That is where we look first on any older coastal roof, and it is where a new roof needs the most thought.

The house matters as much as the town. A home on the sand at Carbon Beach or Broad Beach, or on the bluffs above Point Dume, lives in a different environment from one tucked into a canyon a mile or two inland. Malibu West, the hillsides above Big Rock and the streets off Malibu Road each sit somewhere along that range. That is why coastal metal roofing in Malibu is never one recipe. The right answer is not "metal is good near the ocean." It is "which metal, with which finish and which fasteners, for this address."

Aluminum, Galvalume or Coated Steel

Standing seam panels are made from a few base metals. Each has its place, and on the coast the differences show up over years rather than months.

Copper and zinc are also used as roofing metals and age beautifully, but they bring their own design and cost questions and are a different conversation. Most Malibu coastal projects we discuss come down to aluminum or Galvalume.

Read the Coastal Clause

Here is the detail that surprises people most. Many coated-steel panel warranties restrict or exclude homes within a set distance of salt water, and that distance varies from one manufacturer to the next. Some finishes have a separate, shorter coastal warranty. It is never a reason to panic. It is a reason to read the paperwork before choosing the material, not after. When we propose a coastal roof we point to the clause in the product documentation and explain what it means for your address.

Fasteners, Clips and Dissimilar Metals

A standing seam roof is held down by clips that sit under the seams, plus fasteners at the trim and edges. On the coast those small parts deserve as much attention as the panels.

• Stainless fasteners and clips. A plain or lightly coated fastener can corrode long before the panel does, staining the roof and loosening its grip. Stainless steel hardware is the usual answer near the water.
• No mixing of incompatible metals. When two different metals touch with salt water between them, one corrodes faster. This is galvanic corrosion, and it is one of the most common causes of early trouble on coastal roofs.
• Watch what runs off onto the roof. Water running from copper, or from lead flashings, onto Galvalume can eat at the coating over time. Gutters, chimney caps and old flashings all count.
• Separate what has to touch. Where a dissimilar metal cannot be avoided, it gets isolated so the two never sit in a wet joint together.

We fabricate our panels and trim in our own shop in Van Nuys and choose the hardware for each roof, so the metals on your house are chosen together rather than assembled from whatever was on the truck.

Finishes and Cut Edges

The paint on a metal panel does more than set the color. PVDF finishes, often sold under the Kynar 500 name, are widely used on architectural metal because they hold their color and resist chalking in strong sun. That matters on the coast, where UV and salt work on the finish together.

Where coated steel is used, cut edges are the vulnerable spot, because cutting exposes the steel inside. Clean cuts, the right edge details and hems that fold the edge back on itself all help. It is one of the reasons panels on a coastal roof should be cut and formed with care rather than trimmed roughly in place.

Wind at the Bluff Edge and on the Sand

Salt is not the only coastal force. Homes on the bluffs at Point Dume, along La Costa and Escondido Beach, or on the open sand of the Malibu Colony see stronger, more direct wind than homes in the canyons. Wind pulls up on the edges and corners of a roof hardest, which is where uplift starts.

A standing seam roof handles wind through its attachment: clip type, clip spacing and how the edges and corners are secured. Those are set for the exposure and the roof, not guessed. On an exposed site we pay particular attention to the eaves, rakes and ridge, because that is where wind gets its first hold.

Permits, Views and Neighbors

All of Malibu is in the California coastal zone. The city has a certified Local Coastal Program, which lets the City of Malibu review and issue coastal development permits locally, with some decisions appealable to the California Coastal Commission. Whether a particular reroof needs a coastal development permit, or qualifies for an exemption, depends on the property and the scope of the work, so confirm it with the City of Malibu early. We handle the building permit as part of every job and coordinate on the rest.

Views matter here too. A new roof that changes height, shape or color can matter to neighbors and to the city. Replacing a roof in the same form usually keeps those questions simple, but it is worth talking through before a design changes. A low-slope standing seam roof can keep a house's profile low, which is one reason it suits so many coastal homes.

Coastal and Fire, Together

Every Malibu home deals with both salt and wildfire, and good coastal choices support fire performance. A corroded edge or a loose fastener can open a gap in a roof built to keep embers out. For the fire side of the decision, including Class A assemblies and the state's wildland-urban interface rules, see our page on fire-resistant metal roofing in Malibu.

How We Approach a Coastal Roof

We have been fabricating and installing standing seam since 2006, and we are a residential roofer only. Our specialty is custom-fabricated standing seam, made in our own Van Nuys shop and installed by our own crew, with no subcontractors. On a coastal project that means the person who chose your fasteners is the same company that installs them. You can read more about us on our main site, Eclipse Metal Roofing.

Good coastal metal roofing in Malibu starts with a visit, not a catalog. We look at where the house sits, how it faces the water and the wind, what is on the roof now, and where salt has already left its mark. Then we recommend a material, a finish and a set of details, and explain why.